The temporary hearing loss induced by exposure to intense sounds is increased if a person takes moderate doses of aspirin or sodium salicylate for two or more days prior to the exposure. The implication of this outcome is that people who live or work in noisy environments and who use either of these drugs may be at greater risk of permanent hearing loss than are people who receive the same noise exposures, but do not use the drugs. Two other non-steroidal anti-inflammatory agents, sulindac and diflunisal, do not produce this effect when taken in comparable doses. The goal of the proposed research is to examine other common drugs of various types for their ability to potentiate exposure to intense sounds, and to further study the various effects of aspirin on the auditory system. The other drugs of primary interest are widely used anti-inflammatories and analgesics. Establishing the relative safety of these various aspirin subtitutes will be of value to consumers, and to physicians when prescribing drugs for patients who live or work in noisy environments. Knowing more about the various auditory effects of aspirin may provide insights into the basic mechanisms of hearing, and it definitely will allow a reasoned decision as to whether the aspirin-altered ear is an acceptable model of certain auditory pathologies. The basic methodology used is a variant on the standard procedure for studying noise-induced, temporary hearing loss. The intensity of a tone is increased across daily sessions until it produces the target amount of temporary hearing loss (14 plus or minus 3 dB). Once established for each subject individually, those intensities are used to determine baseline values of exposure-induced temporary hearing loss. Then the drug of interest is administered, the same exposure intensity is delivered, and the total temporary hearing loss induced is measured and compared to the baseline function. Each crew of four listeners typically serves in three drug conditions, run at two-week intervals. No exposure ever exceeds 110 dB for 15 minutes. The informed consent procedure includes an educational program of required lectures, films and readings.